A proposed 550-megawatt transmission line that connect the power grids on the Olympic Peninsula and Vancouver Island has received the approval of the U.S. Army Corps of Engineers -- which removed the last hurdle for construction on the American side of the Strait.

The Sea Breeze Pacific Juan de Fuca Cable LP's line would leave Vancouver Island from Esquimalt, near Victoria, and connect with Port Angeles near the former Rayonier Inc. pulp mill site, located at the end of North Ennis Street on the city's waterfront.

Construction of the estimated $350 million project is expected to begin in mid- to late-2009, said Sara Mitchell, project coordinator with the Vancouver, British Columbia-based Sea Breeze Power Corp., which conceived of the cable in 2004.

Construction could take up to 18 months, she said.

The Army Corps of Engineers permit authorizes the cable to be constructed on U.S. soil and seabed.

In September, Sea Breeze also received a permit from the state Department of Ecology, which laid out the water quality and pollution requirements of the project.

The U.S. Department of Energy issued Sea Breeze a Presidential Permit, which addresses impacts on the environment and U.S. electric transmission system, on June 12.

Sea Breeze claims that both the Corps of Engineers permit and the Canadian National Energy Board permit issued in September 2006 are firsts for a private-sector led international transmission project.

Energy from the island

The cable would allow Sea Breeze to sell energy, particularly renewable energy, into the United States from Vancouver Island.

Sea Breeze Power Corp. has a 450-megawatt wind farm permitted on Vancouver Island and a 25-megawatt run-of-river hydro project in the permitting process on the Canadian mainland, said the company's Web site, www.jdfcable.com.

The cross-border transmission line along the I-5 corridor is considered congested, Mitchell said.

"The big factor is renewable energy demand in the [United States]," she said.

Another $150 million in electrical system upgrades are expected to be needed to handle the additional capacity that would come from Vancouver Island.

How that cost may be distributed has yet to be determined, Mitchell said.

Mitchell said Sea Breeze still needs:

âñ An aquatic land lease agreement with the state Department of Natural Resources.

âñ A renewed noise variance for construction from the city of Port Angeles.

The variance was approved in 2006, but has since expired.

It allowed Sea Breeze to conduct 23 consecutive days and nights of tunnel boring on Liberty Street between Caroline and Georgiana streets, about three blocks east and one block south of Olympic Medical Center.

âñ Storm water and building permits.

âñ An environmental assessment from three Canadian federal agencies.

Ecology & Environment Inc. from Seattle is consulting with Sea Breeze on all of its U.S. permits.

Mitchell said the company is still seeking a lease agreement with Clallam County Public Utility District for the construction of a converter station adjacent to the Peninsula College campus in Port Angeles.

Construction of the cable was initially expected for early 2007.

Mitchell said Sea Breeze didn't expect the permitting process to take this long, particularly on the Canadian side.

A private-led submarine trans-border cable project is unique to Canadian and U.S. federal agencies, which is why the permitting has taken longer than expected, she added.

"There is not a precedent for this," she said.

A ship-towed machine would dig a trench between three feet and six feet deep to lay the cable under the Strait and cover the trench.

On land, the cable would be about eight inches thick. It would be 10 inches in diameter under water.

Mitchell said a horizontal directional drilling machine would be used to drill 700 to 800 meters under the harbor's shoreline and other environmentally-sensitive areas to connect with the cable.

The machine would likely need to operate on the Rayonier site, she added.